We are all unique, at least we like to think so….
In the era of ‘personalized medicine’ or ‘precision medicine’ we would like to think that we all get individual treatment based on our genetic code.
To really understand what makes us unique, we have to start back at the beginning and look at what makes a gene, a gene. For the uninitiated, a ‘gene’ is a combination of one of four building blocks (let’s say bricks) aligned in a specific manner. Individually they are pretty insignificant but together, with the right building plans and right architect they can come together to create: a conservatory, a house or a palace! To those who may know more, the DNA bases (7 billion in total) form to create approximately 10,000 genes in the human body and are controlled by a variety of genetic mechanisms. A simple explanation, but in reality it is much more complicated as genes are regulated and affected by a variety of different factors such as: promoters, methylation, miRNA….
Complexity aside, with tremendous advances in genetic tests and “sequencing” whereby the entire building blocks of yourself can be decoded for less than $1,000, can you hide anything? And how can everyone be unique if there are just 10,000 genes that could potentially differ?
Different classes of genes
To explain a bit more. Some things are predetermined, and in the case of genetic diseases it is a fact that your genes do in fact make you who you are. Colour blindness and Huntingdons are examples of this whereby it is a discrete genetic disease. Ie. you have it or you don’t. Other genetic diseases can increase the percentage chance of getting a condition (polygenic) and Angelina Jolie’s breast cancer story is a great case of this, causing her to undergo significant surgery in order to reduce her chance of receiving the disease – but wasn’t guaranteed.
It’s a lot more complicated than attributing certain genes or the environment to the phenotype of a person. For example, studies have shown that there are multiple genes involved in obesity and that mice who have the specific genetic changes become hungrier (and therefore eat more). However, without the environment ‘factor’ (food in this case), then the phenotype (obesity) would not have been able to be expressed from the genotype (the genetic code)….
Fortunately, or unfortunately depending on how you see it, scientists are a long way from being able to link every gene to a specific pre-disposition, let’s say to ‘violent behaviour’ or ‘dementia’. Although big advances have been made, there are quite simply too many variables that affect what makes you unique beyond that of your genetic code (environment, epigenetics etc. etc.) and the “big data” is actually too overwhelming to decipher. There’s a great little video on it here.
This data does have one big, actually, huge benefit of namely Personalized Medicine. When we talk about personalized medicine, are we talking about an individual? Probably not. It is semantics at the end of the day but the word ‘personalized’ insinuates that every individual is getting a different treatment whereas that is far from the case with millions receiving identical medicine cocktails. Working in marketing as I do, perhaps a more apt terminology would be “segmented medicine” where patients are categorised as responders and non-responders.
Notably, one of the biggest genetic sequencing projects in the world was the ‘Human Genome project’ creating this data completed back in 2000, where there was hope that genetic markers would clearly segment patients into responders and non-responders. However, this has not yet happened, in part because complex traits are highly polygenic (see here)
Is there a thing as too much knowledge?
All this data provides an ethical dilemma: would you want to know if you are going to die at 40 (Huntingdon’s) or that you have an increased chance of breast cancer (BRCA mutation)? An insurance company certainly would. Imagine the effects, not only on yourself but on your friends and colleagues. If you knew you/society were going to die young:
- Would you be less likely to get that promotion at work if your boss found out? Probably
- Would you take out a large life-insurance policy? Probably
- Or would the life insurance company let you take one out if they knew? Probably not!
Interestingly, 23andme is at the forefront of the ‘genetic revolution’ and providing genetic data to the lay public (ie. You and me) for a ~mere $150 and will tell you a myriad of traits that may affect your life’s decisions. I’ve not taken one, would you?
Minority report and the future
So bringing it back to the start: what does this mean to you and do your genes make you who you are and where is the future heading? Many of you may have seen Tom Cruise in the film ‘Minority Report’ where crimes could be pre-determined before they happened and although we are talking about future-prediction versus genetic-makeup, the film perhaps has scary elements of truth interlaced throughout.
We can already take educated guesses at how people will turn out and the diseases they will face later in life and this technology is only ever going to become more accurate. Fortunately, or unfortunately (?) we’re not yet at the stage to conclusively say that genes ‘maketh the person’, but maybe the question you should be asking instead should be:
“How will society use your genetic data in the future?”